Paul provides two ways to recognize the Spirit's presence in worship:
Those who curse Jesus show they reject him and his message, so they cannot speak by the Spirit of God.
Believers show the Holy Spirit's presence in their lives by sincerely confessing that Jesus is Lord. This may be the earliest Christian creed (see Romans 10:9, 13; 2 Corinthians 4:5; Philippians 2:11; 1 John 4:2–3).